A wide variety of machinery exists in working conditions throughout the world and is exposed to abrasive and stressful conditions. Large work loads, open and corrosive conditions and time all work to wear out bearing surfaces and require replacement and or repair. For large bearing surfaces, there is often a need to buildup material in the inner surface of a bearing bore. Various attempts have been made to provide automated machinery for depositing welding beads in a uniform manner on the inner bores of bearing journals.
For instance, U.S. Pat. No. 4,527,039 to Fuwesi teaches and apparatus and method for restoring the surfaces blind or through surfaces of metallic workpieces. Fuwesi teaches a method be which tools, including welding torches, can be connected to a rotating spindle. The effective radii of rotational movement of the welding torch in Fuwesi is fixed by combination of a length of the welding attachment itself, and the spindle mechanism. Fuwesi does not disclose a manually adjustable axial positioning mechanism.
U.S. Pat. No. 4,687,899 issued to Acheson teaches an apparatus for restoring the inner surfaces of bores in metallic workpieces that has an adjustment means that relies on fixed pieces connected with a gear mechanism for adjusting the effective radii of the welding torch. This mechanism will be either quite large or will have a small range of adjustable radii. As another embodiment Acheson's apparatus, there is provided two part mechanism for adjusting the radius of the welding arm, a radial arm and an arm parallel to the axis of rotation of the axis of the apparatus. It is clear that Acheson requires several embodiments of the device in order to provide a wide range of radii.
U.S. Pat. No. 5,298,710 issued to Acheson also teaches an apparatus for building up material in a large bore of a metallic workpiece. In developing the Acheson technology of previous patents, including U.S. Pat. Nos. 4,873,419; 4,892,990; and 4,925,769; Acheson has relied upon additional setups to provide a greater radii range and has developed and claimed a specific method of sweeping the inner bore that sweeps approximately 359 degrees and then makes a step, effectively equal to the welding bead.
Each of the systems is complicated and requires careful attention to setup parameters in order to insure proper operation. The typical trend has been to make devices that are capable of doing many operations, including building up bore surfaces and little attention has been paid to providing equipment that is responsive to the needs and conditions imposed by day to day operations. However, none of the prior art references are specifically configured to be easy to set up in the field, their primary working condition. Each of the systems is complicated and requires careful attention to setup parameters in order to insure proper operation.